         ~@(when state
             '(:init "init" :state "state"))
         :extends ~(or extends Activity)
+        :implements ~implements
         :exposes-methods {~'onCreate ~'superOnCreate
                           ~'onStart ~'superOnStart
                           ~'onRestart ~'superOnRestart


  Available optional arguments:

  :extends, :prefix - same as for `gen-class`.

  :features - window features to be requested for the activity.
  Relevant only if :create is used.


  :on-start, :on-restart, :on-resume, :on-pause, :on-stop, :on-destroy
  - same as :on-create but require a one-argument function."
  [name & {:keys [extends implements prefix on-create on-create-options-menu
                  on-options-item-selected on-activity-result
                  on-new-intent def state key features]
           :as options}]
